RHEA COUNTY, Tenn. (WTVC) - Investigators with the Rhea County Sheriff's Department arrested a couple for aggravated child abuse.

Det. Rocky Potter tells NewsChannel 9 the 5-year-old victim's mother, Monica Hall, and her boyfriend, Dennis Couch, restrained him to the floor using a medium-sized dog harness attached to a man's belt and fastened with electrical tape. The harness was attached to a U-bolt on the floor.

"When you think that you've heard it all or seen it all, then I get something like this," said Potter. "This is the first case where a restrain device was used on a child."

Potter says police got a tip through a child abuse hotline that a boy with mental disabilities was being abused. A family friend told the child's mother if she didn't stop with the harness they would call police.

Detectives went to the home and found enough evidence to arrest the couple. According to Potter, Hall and Couch put the boy in the harness for hours at a time for the last three months.

"There was a very distinct reaction when he saw me hold the harness," said Potter when talking about the 5-year-old. "Fear. It was fear."

Potter says the child isn't verbal and could only string together a few words at a time. He heard him yelling, "out, out" and "hungry, hungry" when he went to the house.

"DCS has been involved with this mother and her children before," said Potter. "Nothing this severe. But she is in their system."

According to Potter, the harness was sometimes used as punishment. He would not elaborate any more on Hall's explanation for the harness.

Potter says two other children were in the home at the time. The Department of Children's Services removed all the children. Potter says they are staying with relatives.

District Attorney Mike Taylor says the boy was "particularly vulnerable" because he has a mental disability that renders him mostly non-verbal.

Potter says the couple will appear in court on Aug. 4.

An arrest report says Couch also faces felony charges related to manufacturing methamphetamine. He was already on probation when deputies arrested him Monday. When they got to the house, they found him in a makeshift room on the property with needles, spoons and a white substance.

According to Potter, the boy had a wellness check at Children’s Hospital at Erlanger Tuesday.

This is a developing story. Depend on us to bring you details as we get them.